Discarded tyre rubber as concrete aggregate: a possible outlet for used tyres

Discarded vehicle tyres constitute one important part of solid waste which had historically been disposed of
into landfills. Recent EU policies on the Landfilling of Waste (Council Directive 1999/31/EC) have however
put a ban on the landfilling of whole or shredded tyres, creating an imminent need to investigate any
possible viable uses of this waste product. An emerging use is the production of concrete, in which tyre
rubber particles partially replace natural aggregates. This has the additional advantage of saving in natural
aggregates used in the production of concrete which are becoming increasingly scarce. This research
investigated a wide range of physical and mechanical properties of concrete containing recycled tyre
aggregates, to assess its suitability as a construction material. The influence of factors such as rubber
aggregate content and size, as well as curing time was also considered. The results showed that despite a
great loss in strength, this type of concrete was acceptable for various applications requiring medium to low
compressive strength. The quantities of concrete produced worldwide for such applications could ensure
the viability of this product. Therefore, this type of concrete shows promise for becoming an additional
sustainable solution for tyre rubber waste management.